Full context:   According to Grzegorz Polak, the four upassanā (foundations of mindfulness) have been misunderstood by the developing Buddhist tradition, including Theravada, to refer to four different foundations. According to Polak, the four upassanā do not refer to four different foundations, but to the awareness of four different aspects of raising mindfulness: The Greek philosophical school of Stoicism founded by Zeno of Citium included practices resembling those of mindfulness, such as visualization exercises. In his Discourses, Stoic philosopher Epictetus addresses in particular the concept of attention (prosoche), an idea also found in Seneca and Marcus Aurelius. By cultivating it over time, this skill would prevent the practitioner from becoming unattentive and moved by instinct rather than according to reason.